Objectives: The epidemiology of gastrointestinal stromal tumor has not been well examined, and prior studies often provide conflicting results. We conducted the first population-based study to evaluate the incidence and survival of malignant gastrointestinal stromal tumor in the United States.
Methods: We utilized the Surveillance, Epidemiology, and End Results registry from the National Cancer Institute to identify all cases of malignant gastrointestinal stromal tumor diagnosed from 1992 to 2000. The age-adjusted incidence rates and the survival rates were calculated. Cox proportional hazards models were used to examine the risk of mortality.
Results: Between 1992 and 2000, there were 1,458 cases of diagnosed gastrointestinal stromal tumor. The age-adjusted yearly incidence rate was 0.68/100,000. The mean age at diagnosis was 63 yr. Fifty-four percent were men and 46% were women. The incidence rate was higher among men and among Blacks. Fifty-one percent of cases were in the stomach, 36% small intestine, 7% colon, 5% rectum, and 1% in the esophagus. Fifty-three percent of cases were staged as localized, 19% regional, 23% distant, and 5% unstaged. The 1- and 5-yr relative survival rates were 80% and 45%, respectively. The Cox analysis showed that older age, Black race, advanced stage, and receipt of therapy were independent predictors of mortality.
Conclusions: Malignant gastrointestinal stromal tumors rare, but are more common in the older population, men, and Blacks. Risk factors for mortality include older age, Black race, advanced stage, and no surgical intervention.